Gas-engine starter



1,625,793 p l 1927' R. H. CHILTON GAS ENGINE STARTER Filed Nov. 16. 1920 2 Sheets- Sheet 2 L ,ZhvenfOW: Pal 0h H. Chi/fon ATTORNEY Patented Apr. 26, 1927.

RALPH H. CHILTON, 0F TOLEDO, UHIO, ASSIGNOR T0 INDUSTRIAL RESEARCH COR- PORATION, 0F TOLEDO, OHIO, A CORPORATION OF DELAWARE.

GAS-ENGINE STARTER.

Application filed November 16, 1920. Serial No. 4124,451.

This invention relates tostarting mechanism for engines, particularly of the type which are normally non-selfstarting such as internal combustion engines.

'l he invention contemplates the employment of an automatically meshing and demeshing gear wherein the shock of meshing is absorbed by a compression element, in distinction from a tension element.

An important object is the provision of. a resilient element in the drive connection which has the double function of absorbing variations in load between the driving and driven members, and alsopreventing injury to the gears through improper meshing.

A further object is the utilization of a spring element which is more freely yieldable and resilient when compressed due to improper meshing than when transmitting power.

Still another object is the provision of a resilient element in a starter drive which is not subject to breakage.

Further objects and objects relating to economies of manufacture and details of construction will definitely appear from the detailed description of the invention.

Various preferred modifications of the invention appear in the accompanying drawings in which:

Figure l is a longitudinal section through the drive mechanism;

Figure H is a transverse section of the device shown in Figure I;

.Figure HI is a view showing a metallic spring connection;

Figure IV is transverse section of the modification of Figure 1H; I

Figure V is plain sectional view of the mechanism of Figure 1H:

Figure Vl shows a modified type of drive spring;

Figure VII is a modification in longitudinal section wherein the sleeve and pinion both have bearing on the shaft: Figure VIII shows the device of Figure VH with a metallic spring employed.

Figure IX is a modification of the arrangement of Figure VH showing the use of metallic springs.

Referring to Figure I the shaft 10 is extended from any conventional power source such as an electric motor 11 and screw threads 12 are cut thereupon. In meshing ternally threaded'sleeve 13 on the outer surface of which ridges M are formed extending axially thereupon. These ridges 14; are adapted to be positioned in axial channels .or grooves 15 cut on the inner surface of pinion 16. These channels 15 have a width in excess of that or the ridges M and in this excess space-between the ridges and one wall of the channels is interposed a resilient element 17 consisting of cork, rubber or fabricated material.

The channels 15 do not extend completely across the pinion, a portion 18 of the material of the pinion remaining in place at one end of the channels, the other end being open. At the open or outer ends of the channels plates 19 attached to the sleeve by screws 20 serve to block the channels and hold the resilient material in place.

It is evident that with the above described arrangement of parts, the pinion has rotatable and axial movement on the sleeve limited only by the yield of the resilient material in the pinion channels; and since the yielding material has greater dimensions axially than transversely there is greater yield in an axial than in a transverse direction.

in the operation of the device when the motor shaft is rotated in the direction of the arrow in Figure H the sleeve and pinion move as a unit, with very limited rotation, it any,

' axially along the shaft and into mesh with the engine member. As soon as the sleeve is stopped by the collar 21 it tendsto take on the rotary speed; of the drive shaft, but since the pinion is restrained by the load it is prevented froinacquiring the motor speed until the inertia-of the engine is overcome. By means of the yielding element 17 the shock incident to taking up the. engine load is largely absorbed and the drive is then yieldingly carried on through the resilient element.

lln case the pinion teeth in moying toward the engine gear fail to mesh properly therewith, the teeth abutting each other, the

mechanism is injuredv or made inoperative unless the parts yield sufficiently to allow slight rotation of the pinion subsequent to which proper meshing occurs. It is desirable that this axial yield of the pinion be free and in practice it has been found necessary in related devices to employ separate spring means of greater flexibility than the drive springs. lln this mechanism however sleeve 3l'enters a transversely extending groove 32 in the pinion interior and a coiled spring 33 in this groove normally holds the tongue at the rear end'of the groove when rotating to start the engine. A resilient element 34 formed of spring metal or yielding fabric and placed between the pinion and sleeve stops 35 serves to retain the pinion against an inner limiting stop 36 on the sleeve 31 in order toallowaxial yield when the gear teeth fail to mesh as was indicated with reference to the preferred form of drive.

In Figure V means for eliminating the yielding element 34 is shown. In this arrangement the tongue 37 and groove 38 are placed at an angle with the shaft axis and the coil spring 39 placed so that it normally tends to hold the pinion in inward position. When either the load is taken up or the teeth abut in starting the sprin com resses and the pinion slides outwardly an rear wardly.

Figures VII and VIII illustrate a modi fied form wherein the pinion 40 is positioned directly on this drive shaft instead of the sleeve. As here shown the sleeve 41 is screw threaded to the motor shaft and the pinion 40 secured theretoby means of pins 42 slidably and loosely mounted in holes 44 drilled axially in the sleeve element. The v holes 44 have for a greater part of their length a diameter in excess of the pins 42 and in the excess space resulting yielding material 45 is inserted completely surrounding the pins.

In the operation of this modification the drive is from the shaft through the sleeve 41, the ins 42 and pinion '40 to the engine shaft, tie drive shock being taken up by the yielding material 45.

Inthe modification of Figure IX the coil spring 50 is substituted for the yielding material, 45 of Figure VII.

I claim as my invention 1. In an engine starter, the combination i,ea5,793

of a drive shaft; a sleeve on the shaft having both rotatable and axial movement; a pinion having limited axial and rotatable movement on'the sleeve; and a rubber driving connection between the sleeve and pinion, said connection being adapted to hold yieldably the pinion at one limit of its axial movement on the sleeve and forming a driving connection between the sleeve and pinion, and said sleeve having a shorter torque radius than that of the pinion.

2. In an engine starter, the combination of a drive shaft; a sleeve on the shaft having both rotatable and axial movement; a pinion having limited axial and rotatable. movement on the sleeve; and a yielding driving-connection between the sleeve and pinion, said yielding connection being adapted to hold the pinion at one limit of its axial and rotatable movement on the sleeve and forming a driving connection between the sleeve and pinion, said yielding connection being contained within and protected by said pinion, and said sleeve having a shorter torque radius than that of the pinion.

3. In an engine starter, the combination of a drive shaft; a sleeve on the shaft having both rotatable and axial movement; a pinion having limited axial and rotatable movement on the sleeve; a yielding driving connection between the sleeve and pinion said yielding connection being adapted to yield more freely in an axial than in a transverse direction and forming a driving connection between the sleeve and pinion, said yielding connection being contained within and protected by said pinion, and said sleeve having a shorter torque radius than that of the pinion.

4. In an engine starter, the combination of a drive shaft; a sleeve mounted for axial and rotatable movement on the shaft, said sleeve having axially extending ridges formed thereon; a pinion slidably and rotatably mounted on the sleeve, said pinion having axial channels in its inner surface adapted to receive and engage said sleeve ridges; and a yielding resilent element interposed in said channels and in juxtaposition with said ridges, said resilient element forming both a yielding driving connection between the sleeve and pinion, and a yielding element for permitting relative axial movement of the sleeve and pinion.

In testimony whereof, I aflix my signature.

RALPH H. CHILTON. 

